Persistent downregulation of calcium-sensing receptor mRNA in rat parathyroids when severe secondary hyperparathyroidism is reversed by an isogenic kidney transplantation

Experimental severe secondary hyperparathyroidism (HPT) is reversed within 1 wk after reversal of uremia by an isogenic kidney transplantation (KT) in the uremic rats. Abnormal parathyroid hormone (PTH) secretion in uremia is related to downregulation of CaR and vitamin D receptor (VDR) in the parathyroid glands (PG). The aim of this investigation was to examine the expression of CaR and VDR genes after reversal of uremia and HPT in KT rats. 5/6 nephrectomized rats were kept on a normal or high-phosphorus (hP) diet for 8 wk to induce severe HPT (n = 8 in each group). In another group of seven uremic hP rats, uremia was reversed by an isogenic KT and PG were harvested within 1 wk posttransplant. Plasma urea, creatinine, total calcium, phosphorus, and PTH levels were measured. Parathyroid CaR and VDR mRNA were measured by quantitative PCR. Uremic hP rats had significantly elevated levels of creatinine, urea, and phosphorus (P < 0.001) and developed significant hypocalcemia (plasma calcium 1.83 +/- 0.2 mmol/L; P < 0.001) compared with normal control rats. After KT, the levels were normalized from day 3 to 7: creatinine from 0.117 +/- 0.016 to 0.050 +/- 0.002 mmol/L; urea from 23 +/- 4 to 7 +/- 0.3 mmol/L; phosphorus from 3.9 +/- 0.6 to 1.5 +/- 0.06 mmol/L; calcium from 1.8 +/- 0.2 to 2.5 +/- 0.02 mmol/L. Plasma PTH levels fell from 849 +/- 224 to a normal level of 38 +/- 9 pg/ml (P < 0.01). In uremic rats on a standard diet, CaR mRNA was similar to that of normal control rats, whereas VDR mRNA was significantly decreased. In uremic rats kept on hP diet, CaR mRNA was significantly decreased to 26 +/- 7% of control rats (P = 0.01) and VDR mRNA reduced to 36 +/- 11% (P < 0.01). In KT, previously hP uremic rats, both CaR mRNA and VDR mRNA remained severely reduced (CaR, 39 +/- 7%; VDR, 9 +/- 3%; P < 0.01) compared with normal rats. In conclusion, circulating plasma PTH levels normalized rapidly after KT, despite persisting downregulation of CaR and VDR gene expression. This indicates that upregulation of CaR mRNA and VDR mRNA is not necessary to induce the rapid normalization of PTH secretion from hyperplastic parathyroid glands.     

Primary mucosal malignant melanoma of the head and neck

INTRODUCTION: The relative rarity of mucosal melanomas of the head and neck (MMHN) has made analysis of treatment approaches difficult. Advances in diagnostic techniques and treatment interventions have had obvious impact on outcomes in cutaneous melanoma, but the effects on outcome in MMHN remain undefined. This study aims to assess the outcome and identify clinical and histologic prognostic indicators in a recent cohort of patients with MMHN treated at a single institution. METHODS: The clinical records of 59 patients with the diagnosis of MMHN treated at Memorial Sloan-Kettering Cancer Center (MSKCC) between 1978 and 1998 were retrospectively reviewed. Pathologic material on each of these patients was prospectively reviewed by at least two pathologists (MP, KB, or AH) for confirmation of diagnosis and assessment of histologic variables. Survival was calculated by the Kaplan-Meier method. Clinical (patient demographics, tumor characteristics, and treatment) and histologic data (tumor thickness, melanosis, melanoma in situ, vascular invasion, and multifocality) were analyzed for impact on outcome by both univariate and multivariate analyses. RESULTS: Thirty-five patients (59%) had sinonasal tumors (SNMM), whereas 24 (41%) had oral (ORMM) tumors. Forty-seven patients (79.6%) were staged as stage I, 8 (13.6%) as stage II, and 4 (6.8%) were classified as stage III. Regional lymphatic metastases at presentation were more frequent in ORMM compared with SNMM (25% vs 6%, p =.05). Surgery was used in all patients. Adjuvant radiation therapy was used more frequently in the SNMM group compared with the ORMM group (40% vs 17%, p =.04). The rates of local failure for ORMM and SNMM were 51% and 50%, nodal failure rates were 42% and 20%, and distant failure rates were 67% and 40%, respectively (p = NS). With a median follow-up of 20 months, the 5-year disease-specific survival rate was 44% (40% for ORMM vs 47% for SNMM, p = NS). Significant prognostic factors for disease-specific survival on univariate analysis included advanced clinical stage at presentation, tumor thickness greater than 5 mm, presence of vascular invasion, and development of nodal and distant metastases. On multivariate analysis, however, regional nodal failure lost significance. CONCLUSIONS: Clinical stage at presentation, tumor thickness greater than 5 mm, vascular invasion on histologic studies, and development of distant failure are the only independent predictors of outcome in MMHN.     

Radiation-induced osteosarcoma of the chest wall

A case of radiation-induced sarcoma of the chest wall is reported. Twenty-seven years 11 months after orthovoltage radiotherapy of the right breast a 69-year-old woman developed a radiation-induced osteosarcoma of the right thoracic wall. Initial diagnosis has been T-cell lymphoma of the skin. The right breast was irradiated with tangential fields and a total dose of 40 Gy, 2 Gy/day, 5 days a week. Orthovoltage treatment was performed in two courses of 20 Gy, 3 months apart. The clinical appearance of the secondary sarcoma was a diffuse infiltrated area in the irradiated breast which seemed to be fixed to the chest wall. Magnetic resonance imaging (MRI) demonstrated a mass in the right anterior thoracic wall which destroyed the fourth to the sixth rib. The tumor infiltrated the thoracic wall, including subcutaneous tissue and pericardium, as well as extending into the subphrenic space. Biopsy of the lesion revealed a poorly differentiated osteosarcoma. The patient's general condition precluded surgical or chemotherapeutic intervention; she died due to a cerebral stroke 6 months later. This case fulfilled all criteria for radiation-induced sarcoma, as there was a prior history of radiotherapy, latency period of several years, development of sarcoma within the irradiated field, and histologic confirmation of sarcoma.     

Malunion of a Complex Fracture of the Distal Radioulnar Joint (DRUJ)

Background: Generating an artificial spontaneous Sauvé-Kapandji situation after malunion of the distal radioulnar joint (DRJU) enables a patient to move forearm and wrist without pain.Case Study: A patient with an extensive combined fracture of the distal radius and ulna accompanied by a subluxation of the ulnar head and an avulsion fracture of the base of the ulnar styloid was treated with external fixator. During follow-up, an artificial fracture was observed at a former pin site. This led to nonunion approximately 3 cm proximal to the ulnar head. Comparable to a spontaneously generated Sauvé-Kapandji situation, the development of this nonunion resulted in a pain-ree situation allowing free movement of forearm and wrist. The extend of motion was 70°/0°80° pronation/supination.     

Sicherheitsaspekte im Internet

Aim of the study: Is it possible to use the Internet as a secure media for transport of telemedicine? Which risks exist for routine use? In this article state of the art methods of security were analysed. Telemedicine in the Internet has severe risks, because patient data and hospital data of a secure Intranet can be manipulated by connecting it to the Web. Conclusions: Establishing of a firewall and the introduction of HPC (Health Professional Card) are minimizing the risk of un-authorized access to the hospital server. HPC allows good safety with digital signature and authentication of host and client of medical data. For secure e-mail PGP (Pretty Good Privacy) is easy to use as a standard protocol. Planning all activities exactly as well as following legal regulations are important requisites for reduction of safety risks in Internet.     

Feasibility of C-Arm-Supported CT Fluoroscopy in Percutaneous Abscess Drainage Procedures

Purpose: Evaluation of C-arm-supported CT fluoroscopy to facilitate percutaneous abscess drainage procedures. Methods: Prospectively, 40 percutaneous drainage procedures were performed either with C-arm-supported CT fluoroscopy or with CT fluoroscopy alone. Hybrid imaging was performed on the CT couch after complementing a CT fluoroscopy scanner with a C-arm fluoroscopy unit. Procedure times, drainage revisions during follow-up, and postinterventional drainage periods were analyzed. Results: When compared with exclusive CT fluoroscopic guidance, a median procedure time of 9 ± 3.7 min versus 14.8 ± 7.3 min was required for C-arm-supported CT fluoroscopy (p < 0.005, t-test). During follow-up, eight drainage catheters had to be revised within the exclusive CT fluoroscopy group, while only two revisions were necessary within the C-arm-supported CT fluoroscopy group. With C-arm-supported CT fluoroscopy, postinterventional drainage periods were reduced (median 13 vs 19 days; p < 0.001, t-test). Conclusion: Compared with exclusive cross-sectional image guidance, C-arm-supported CT fluoroscopy seems to improve placement of abscess drainage catheters to possibly reduce procedure times, drainage catheter revisions, and postinterventional drainage periods.     

Interventional uroradiologic procedures performed using gadodiamide as an alternative to iodinated contrast material

Three patients with either a history of severe allergic reactions to iodinated contrast or marked renal insufficiency underwent interventional uroradiologic procedures using full-strength gadodiamide (Gd) as a contrast agent in place of iodinated contrast material. The procedures were percutaneous access for nephrostolithotomy, antegrade pyelography with placement of a nephroureteral stent, and a diagnostic nephrostogram with exchange of a nephroureteral stent. Gd was visualized fluoroscopically and produced satisfactory digital radiographs without allergic reaction or worsening renal function. Gd can be useful in guiding interventional uroradiologic procedures when iodinated contrast material is contraindicated.     

18F-FET PET for planning of thermotherapy using magnetic nanoparticles in recurrent glioblastoma.

PURPOSE: Thermotherapy using magnetic nanoparticles (nano cancer therapy) is a new concept of local tumour therapy, which is based on controlled heating of intra-tumoural injected magnetic nanoparticles. The aim of this study was to evaluate the usefulness of PET with a recently introduced amino acid tracer O-(2-[18F]fluoroethyl)-]L-tyrosine (FET) for targeting the nanoparticles implantation. MATERIALS AND METHODS: Eleven patients with glioblastoma recurrences underwent MR and FET-PET imaging for planning of the nano cancer therapy. Thereafter, the gross tumour volumes (GTV) were defined, taking into consideration the results of both imaging tools. RESULTS: The MRI-based mean GTV was 24.3 cm3 (range 2.5-59.7) and the PET-based mean GTV 31.9 cm3 (range 5.2-77.9). On the average the MRI identified an additional 8.9 +/- 4.7 cm3 and the FET-PET scan-an additional 16.5 +/- 15.2 cm3 outside of the common GTV (15.4 +/- 11.0 cm3). The mean final GTV accounted to 33.8 cm3 (range, 5.2-77.9). The additional information of FET-PET led to an increase in GTV by 22-286% in eight patients and to a decrease of 23% and 26%, respectively, in two patients. In one patient, the final GTV was defined on the basis of MRI data only. CONCLUSIONS: FET-PET adds important information on the actual tumour volume in recurrent glioblastomas and is highly valuable for defining the target volume for the nano cancer therapy.